Releasing fasteners of the type wherein one end releases an object when a certain force is applied to the other end to prevent breakage or damage of the fastener or an attached object, such as a rope, cable, or line, often require a spring means within the fastener. Most commonly, a female section of the fastener fastens to a mating male portion on the cable, like a cable with a ball end or other mating piece that fits into a female portion of the releasing fastener.
For example, U.S. Pat. No. 602,569 issued to Turner describes a device that utilizes mating male and female parts that release when they are subjected to a force. A tube and clutch interact so that the clutch grips an eyebolt hooked to one end of a spring. The other end of the spring is secured to the farther end of the tube. Under ordinary circumstances, the clutch remains within the tube, but when a certain load exists at the eyebolt end, the clutch is pulled out of the tube and the eyebolt is released.
U.S. Pat. No. 3,014,257 issued to Huffman discloses a device that hooks an object and has spring means to keep the object hooked while being subjected to vibrational stresses.
U.S. Pat. No. 3,171,183 issued to Johnston discloses a fastener with a pair of end members that are adapted for securement. One of the end members has a ball shaped male portion and is held in place by an expandable socket that has a female portion to accept and retain the male portion. A spring holds the expandable socket in the normally closed position.
U.S. Pat. No. 3,413,692 issued to Pressley discloses a fastener that has a linear spring design. A female portion housed in the fastener accepts a ball shaped male portion, which is attached to a cable. At a particular force, the ball shaped male portion and cable are released from the female portion and the fastener.
U.S. Pat. No. 3,952,382 issued to Vaage discloses a fastener that has two hook members that have a spring to bias the hook members open. A sleeve maintains the hook members closed until the sleeve is manually slid away from the hook members so as to allow the hook members to open.
Fasteners that release upon a certain defined load have many applications, such as, but not limited to, the securing of horses during equestrian training and storage, the securing of nautical vessels, and for securing a sail of a ship.
U.S. Pat. No. 602,569 issued to Turner discloses a device that may be adjusted by threading the intermediate cylinder to varying positions versus the inner and outer cylinders; however, Turner does not provide for a way to manually release the secured object. To release the secured object, the undesired load must be met, whether it is met manually or by the introduction of an undesirable load to the device.
Both U.S. Pat. Nos. 3,171,183 issued to Johnston and 3,413,692 issued to Pressley disclose means to fasten to and release from a specially shaped male portion that must conform to the accepting female portion for the fastener to function. The geometric restrictions and limitations of these fasteners limit the end uses and applications of the fasteners; if the desired object to be attached does not conform to the configurations disclosed and required in the patents, the fasteners simply will not perform.
The above mentioned patents do not provide a fastener that may be used for a particular application where the fastener may be set to release from an object at a predetermined load or force, while at the same time having the capability to easily attach or release the fastener manually with one hand.
What is needed is a fastener that fastens with one hand to a variety of objects that do not have to mate with the fastener, wherein the fastener releases upon a predetermined force or load being introduced to the fastener, wherein the fastener may be manually released with one hand, even while the fastener is under load, and wherein the fastener may be adjusted to release at any one of a range of forces.